[Pages] Update Hexo framework guides, solve the deployment failure issue (#18917)

* Update deploy-a-hexo-site.mdx

npm module executable "hexo" is no longer installed globally. Should migrate to using "npx hexo [args]"

* Update deploy-a-hexo-site.mdx about build command

Co-authored-by: Dario Piotrowicz <[email protected]>

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Co-authored-by: Dario Piotrowicz <[email protected]>

Author: ousugo

src/content/docs/pages/framework-guides/deploy-a-hexo-site.mdx

@@ -64,7 +64,7 @@ To deploy your site to Pages:
 | Configuration option | Value           |
 | -------------------- | --------------- |
 | Production branch    | `main`          |
-| Build command        | `hexo generate` |
+| Build command        | `npm run build` |
 | Build directory      | `public`        |
 
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